literal   in smileys block

problem: the smileys block on content submission pages displays the smileys acronyms (":)" ":-)" ":smile:" etc) separated by literal " ", both in the descriptive text beside the smiley and in the images alt and title attributes.

solution: don't check_plain() the descriptive text, and don't add " " to alt and title attributes

patch attached. it also reduces the whitespace between acronyms from 3 to 2, which in my tests with multiple themes is sufficient and doesn't cause linebreaks.

please test, review, and apply. thanks!